Scroll type machines are becoming more and more popular for use as compressors in both refrigeration as well as air conditioning applications due primarily to their capability for extremely efficient operation. Generally, these machines incorporate a pair of intermeshed spiral wraps one of which is caused to orbit relative to the other so as to define one or more moving chambers which progressively decrease in size as they travel from an outer suction port toward a center discharge port. An electric motor is provided which operates to drive the orbiting scroll member via a suitable drive shaft affixed to the motor rotor. In a hermetic compressor, the bottom of the hermetic shell normally contains an oil sump for lubricating and cooling purposes.
Generally, the motor includes a stator which is secured to the shell of the compressor. The motor rotor rotates within the stator to impart rotation to a crankshaft which is normally press fit within the motor rotor. The crankshaft is rotationally supported by a pair of bearings which are supported by a main bearing housing and a secondary bearing housing. The crankshaft includes an eccentric crank pin which extends into a bore defined in a hub of the orbiting scroll. Disposed between the hub of the crank pin and the inner surface of the bore is a drive bushing which rides against a bearing that is press fit within the bore of the hub.
The design for scroll compressors position the central axis of the crankshaft in a vertical or horizontal position. One difference between the vertical and horizontal scroll compressor designs is the lubrication sump and the delivery systems which deliver the lubricant to the various components of the compressor which require lubrication. In a typical vertically positioned compressor, lubricant is stored in the lower portion of the shell with the lower end of the crankshaft being submerged within the sump. The crankshaft has a relatively large diameter centrally located bore which communicates with a radially outwardly inclined smaller diameter bore which extends to the top of the crankshaft. The larger diameter bore acts as a pump to pump the lubricating fluid up the crankshaft into the smaller diameter bore and ultimately to all of the various portions of the compressor which require lubrication.
When the compressor is positioned horizontally, it is not practical to immerse the end of the crankshaft within the lubricant since this would require filling over one-half of the shell with lubricant. The present invention provides the art with a horizontal compressor which includes a typical vertical compressor which has been positioned horizontally. The horizontally positioned vertical compressor is disposed within the shell of a larger vertical compressor to provide the necessary lubrication sump for the horizontal compressor.
Other advantages and objects of the present invention will become apparent to those skilled in the art from the subsequent detailed description, appended claims and drawings.